Method for detecting objects and localizing a mobile computing device within an augmented reality experience

ABSTRACT

A method includes: recording a series of frames; recording a set of motion data representing motion of the mobile device; detecting relative positions of a 3D constellation of objects based on the series of frames and the set of motion data; generating classifications of the 3D constellation of objects by calculating a classification of each object in a set of object classes; calculating a transform aligning the 3D constellation of objects with a 3D localization map; accessing a set of augmented reality assets defined by the 3D localization map; calculating a position of the mobile device relative to the 3D localization map based on the transform and the set of motion data; and rendering the set of augmented reality assets based on positions of the set of augmented reality assets in the 3D localization map and based on the position of the mobile device in the 3D localization map.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application claims the benefit of U.S. Provisional Application No.62/739,024, filed on 28 Sep. 2018, which is incorporated in its entiretyby this reference.

TECHNICAL FIELD

This invention relates generally to the field of augmented reality andmore specifically to a new and useful method for detecting objects andlocalizing a mobile device within an augmented reality experience in thefield of augmented reality.

BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1A and 1B are a flowchart representation of a method;

FIG. 2 is a flowchart representation of one variation of the method;

FIG. 3 is a flowchart representation of one variation of the method; and

FIG. 4 is a flowchart representation of on variation of the method.

DESCRIPTION OF THE EMBODIMENTS

The following description of embodiments of the invention is notintended to limit the invention to these embodiments but rather toenable a person skilled in the art to make and use this invention.Variations, configurations, implementations, example implementations,and examples described herein are optional and are not exclusive to thevariations, configurations, implementations, example implementations,and examples they describe. The invention described herein can includeany and all permutations of these variations, configurations,implementations, example implementations, and examples.

1. Method

As shown in FIG. 1A, a method S100 for rendering augmented realitycontent includes, at a mobile device and during a recording period:recording a series of frames in Block S110; and recording motion datarepresenting motion of the mobile device in Block S112. The method S100also includes: detecting relative positions of a 3D constellation ofobjects based on the series of frames and the motion data in Block S120;generating a set of classification vectors of the 3D constellation ofobjects by calculating a classification vector for each object in the 3Dconstellation of objects, the classification vector representing aconfidence score of the object for each object class in a set of objectclasses in Block S130 and returning the 3D constellation of objects andthe set of classification vectors to a remote computer system in BlockS140. The method S100 further includes, at the remote computer system:calculating a transform aligning the 3D constellation of objects with a3D localization map defining a set of objects characterized by relativepositions and classification vectors matching the relative positions andthe set of classification vectors of the 3D constellation of objects inBlock S150; and returning, to the mobile device, a set of augmentedreality assets defined by the 3D localization map and the transform inBlock S152. The method S100 also includes, at the mobile device,rendering the set of augmented reality assets onto a display based onpositions of the set of augmented reality assets in the 3D localizationmap and based on the transform in Block S160.

As shown in FIG. 1A, one variation of the method S100 includes, at amobile device and during a first recording period: recording a firstseries of frames in Block S110; and recording a first set of motion datarepresenting motion of the mobile device in Block S112. This variationof the method S100 also includes, at the mobile device: detectingrelative positions of a first 3D constellation of objects based on thefirst series of frames and the first set of motion data in Block S120;calculating a classification of each object in the first 3Dconstellation of objects based on the first series of frames in BlockS130; and returning the first 3D constellation of objects and theclassification of each object to a remote computer system in Block S140.The method S100 further includes, at the remote computer system:calculating a transform aligning the first 3D constellation of objectswith a 3D localization map defining a set of objects characterized byrelative positions and classifications matching the relative positionsand the classifications of the first 3D constellation of objects inBlock S150; and returning, to the mobile device, a set of augmentedreality assets defined by the 3D localization map, and the transform inBlock S152. This variation of the method S100 also includes, at themobile device: calculating a position of the mobile device relative tothe 3D localization map based on the transform in Block S162; andrendering the set of augmented reality assets onto a display based onpositions of the set of augmented reality assets in the 3D localizationmap and based on the position of the mobile device in the 3Dlocalization map in Block S160.

As shown in FIG. 1A, another variation of the method S100 includes, at amobile device during a first recording period: recording a first seriesof frames in Block S110; and recording a first set of motion datarepresenting motion of the mobile device in Block S112. This variationof the method S100 also includes: detecting relative positions of a 3Dconstellation of objects based on the first series of frames and thefirst set of motion data in Block S120; generating classifications ofthe 3D constellation of objects, for each object in the 3D constellationof objects, by calculating a classification of the object in a set ofobject classes in Block S130; calculating a transform aligning the 3Dconstellation of objects with a 3D localization map defining a set ofobjects characterized by relative positions and classifications matchingthe relative positions and the classifications of the 3D constellationof objects in Block S150; accessing a set of augmented reality assetsdefined by the 3D localization map and the transform in Block S164;calculating a position of the mobile device relative to the 3Dlocalization map based on the transform and the first set of motion datain Block S162; and rendering the set of augmented reality assets onto adisplay based on positions of the set of augmented reality assets in the3D localization map and based on the position of the mobile device inthe 3D localization map in Block S160.

2. Applications

Generally, Blocks of the method S100 can be executed by a nativeapplication or web browser (hereinafter an “app”)—executing on a mobiledevice—and by a remote computer system to localize the mobile devicewithin a space, to detect objects near the mobile device, and to renderaugmented reality assets—aligned with corresponding objects detectednearby—on a viewfinder of the mobile device in (near) real-time.

In particular, the application can: implement computer vision,artificial intelligence, deep learning, or similar methods andtechniques to detect and characterize objects in a video feed recordedby a 2D color camera on the mobile device; estimate 3D positions ofthese objects relative to the mobile device in individual 2D framesbased on concurrent 2D frames and motion data collected by the mobiledevice; compile 3D position estimates of objects derived from a smallset of contiguous 2D frames into higher-resolution, lower-noisecomposite 3D positions of these objects relative to the camera; andreturn characterizations of these objects and their composite 3Dpositions, as a “3D constellation of objects” to a remote computersystem, such as via a wireless computer network. The remote computersystem can then: compare characterizations of these objects and theircomposite 3D positions to a predefined 3D localization map to determinethe position and orientation of the mobile device relative to a virtualorigin defined in the 3D localization map; access augmented realityassets associated with a space containing this location; and return thelocation of the mobile device relative to the virtual origin andaugmented reality assets—also defined relative to the virtual origin—tothe mobile device in near real-time. The application can then project anaugmented reality asset onto an associated object detected in the last2D frame recorded by the camera based on the position and orientation ofthe camera relative to the virtual origin, the position and orientationof the augmented reality asset defined relative to the virtual origin,and the position and orientation of the object relative to the mobiledevice. Similarly, the application can project augmented reality assetsonto an associated mutable object detected in the last 2D frame recordedby the camera based on the position and orientation of the objectrelative to the mobile device. The application can then render thisaugmented 2D frame on a display of the mobile device (hereinafter a“viewfinder”) substantially in real-time.

Therefore, the application improves upon existing localizationtechnology by localizing mobile devices relative to a virtual originbased on high-level, semantic characterization of objects as opposed torelying solely on low-level, computationally heavy point-cloud-basedlocalization (e.g., via point cloud comparison, surface detection etc.).As a result, the application can localize the mobile device in 3D spacein a similar manner to a human—by identifying relative positions ofidentifiable objects in a space and comparing these 3D constellations ofobjects to know spaces. As a result, the application is less sensitiveto changes in a 3D environment or the ability of the mobile device todetect the 3D environment such as slight changes in the positioning ofobjects or obstructing objects, lighting conditions, or any othertransient effect that may change the 3D environment or the ability ofthe mobile device to detect the 3D environment.

Therefore, the app: can execute on a mobile device; can leverage a localobject detection model—defining a relatively small footprint—to rapidlydetect and characterize objects in 2D frames recorded by a camera in themobile device; and can combine and filter 3D locations of objectsestimated from short consecutive sets of these 2D frames to increaseaccuracy of calculated locations of these objects while limiting latencyof these calculations; and then return these data to a remote computersystem for processing. For example, the mobile device can leverage alocal object detection model trained to output an “object signature”containing a set of scores for likeness of an object to each objectclass in a predefined, ordered set of object classes—rather thanidentify an object as a particular species of many possible species in aparticular object class in many possible object classes. The remotecomputer system can then leverage more powerful remote processing and arelatively large (or “heavy”) 3D localization map to rapidly determinethe position and orientation of the mobile device in real space based onobject location and characterization data received from the mobiledevice. The remote computer system can also aggregate augmented realityassets associated with immutable and mutable objects in a spacecontaining the location of the mobile device and return these augmentedreality assets and the location of the mobile device to the mobiledevice. The application can then leverage these augmented reality assetsand the location of the mobile device to render augmented realitycontent on the mobile device substantially in real-time.

3. Pre-Mapping

In one variation, as shown in FIG. 3, the remote computer systeminterfaces with an operator through an operator app executing on amapping device carried by the operator to construct an initial 3Dlocalization map of a new space and to populate this 3D localization mapwith (or link objects represented in the 3D localization map to)augmented reality assets.

In one implementation, an operator walks around a new space with amobile device executing an instance of the operator app, which captures:a sequence of 2D frames through a camera integrated into the mobiledevice; motion device data synchronized to these 2D frames; and ageospatial location of the mobile device during this pre-mapping period.The mobile device can then implement methods and techniques describedbelow to detect objects in these 2D frames, to calculate their 3Dlocations, to calculate their object signatures, and to then returnthese data to the remote computer system. The remote computer system canthen construct a 3D localization map representing this space, such asincluding locations, types, sizes, and/or signatures (i.e.classification vectors), etc. of objects detected throughout this spaceover this pre-mapping period and defined within the 3D localization maprelative to a common virtual origin, such as static or immutable objectsonly. The remote computer system can also label each objectrepresentation in the 3D localization map as either static (e.g.,possibly immutable) or moving (e.g., mutable) based on whether theremote computer system or the operator app determined that the objectwas moving relative to the earth during this pre-mapping period.Alternatively, the remote computer system can label each objectrepresented in the 3D localization map based on a probability of theobject's motion, such as based on prior frames in which an object of thesame or similar signature was detected and whether this similar objectwas determined to have moved between these prior frames; and/or with aspeed, velocity, and/or acceleration of the object. The remote computersystem can further tag the 3D localization map with the geospatiallocation of the mobile device during this pre-mapping period.

More specifically, the operating app can, at a mapping device, during arecording period: record a series of 2D frames capturing an area ofinterest; and record a set of motion data representing motion of themapping device; and return the series of 2D frames and the set of motiondata to the remote computer system. Once the remote computer systemreceives the series of 2D frames and the set of motion data, the remotecomputer system can: identify a set of objects based on the series of 2Dframes and the second set of motion data. The remote computer system canthen, for each object in the set of objects: calculate a location of theobject relative to a virtual origin; and calculate a classification ofthe object. The remote computer system can then generate a 3Dlocalization map based on the location of each object in the set ofobjects relative to the virtual origin and the classification of eachobject in the set of objects. Alternatively, the operator applicationcan execute the above-described steps of the remote computer system atthe mapping device.

Additionally, the operator app and/or the remote computer system cangenerate a 3D point cloud and/or surface map based on the series offrames and/or the motion data recorded at the mapping device and combinethis 3D point cloud map with the 3D localization map to generate acomposite 3D map of an area of interest, which includes detected objectsand their associated locations and signatures in addition to a pointcloud, surface based, or visual map of the area of interest. Bygenerating a composite 3D map, the operator app can identify additionalvisual features in the area of interest and provide more features ontowhich the operator app can map augmented reality assets.

More specifically, the operator app can (e.g., at the remote computersystem): generate a dense set of points representing distances from thecamera of the mapping device to surfaces of an area of interest based onthe set of frames and the set of motion data; generate a dense 3D pointcloud reconstruction of the area of interest based on the dense set ofpoints; and overlay the dense 3D point cloud reconstruction over the 3Dlocalization map to generate a composite 3D map.

However, due to the longer processing time of generating the dense 3Dpoint cloud reconstruction of the area of interest, the operator app cangenerate a sparse 3D reconstruction of the area of interest based on theset of frames and the motion data recorded by the mapping device. Themapping device can, therefore, display the sparse 3D reconstruction to auser of the operator app such that the user may ascertain whether shehas successfully captured the entirety of the area of interest.Therefore, the operator app can generate a 3D reconstruction of thespace that can be quickly visually represented on the display of themapping device in order to improve a user experience of the operator appduring capture of an area of interest. Therefore, a user of the operatorapp may view the sparse 3D reconstruction of the area of interest andidentify an obstruction (or any other problem such as blurring) thatprevented successful capture of the area of interest. Upon identifyingthat the capture of the area of interest was unsuccessful, the user maythen choose to recapture the area of interest via the operator app.

More specifically, the operator app can: generate a sparse set of pointsrepresenting distances from a camera of the mapping device to surfacesof the area of interest based on the second set of frames and the secondset of motion data; generate a sparse 3D point cloud reconstruction ofthe area of interest based on the sparse set of points; and, at themapping device, render the sparse point cloud 3D reconstruction of thearea of interest.

Furthermore, the remote computer system can then interface with theoperator through the operator portal: to upload augmented reality assets(e.g., static or animated augmented reality overlays, audio snippets);to link specific unique objects, object classes, or object species(described below), etc. detected in these 2D frames with these augmentedreality assets; and to define rules for presenting these augmentedreality assets when these objects or like objects are detected by aninstance of the application executing on a mobile device occupying thissame space at another time in the future. Finally, the remote computersystem can store the 3D localization map, the augmented reality assets,and rules linking these augmented reality assets to unique objects,object classes, and object species in a remote database before enablingthis augmented reality experience for other mobile devices in thisspace.

However, the remote computer system can interface with the operatorportal, the mobile device, and the operator in any other way toinitialize a new augmented reality experience for a new space.

4. Object Detection and Localization Summary

Generally, the application executes Blocks of the method S100 inreal-time to detect, track, and characterize objects in 2Dframes—recorded by a single 2D color camera in the mobile device—in(near) real-time. The application can then, in Block S120, assemblethese detected objects, and related characteristics and classificationsof these objects into a 3D constellation of objects that can be comparedto a more dense 3D localization map in order to localize a mobile devicerelative to a known area of interest and to display augmented realityassets placed in this area of interest.

More specifically, the application can: access a stream of 2D framesrecorded by a camera integrated into the mobile device; implementvisual-inertial odometry, structure from motion, deep learning, orsimilar techniques to construct a 3D manifold of surfaces in the fieldof view of the camera based on features detected in this stream of 2Dframes and based on motion of the mobile device over time; implementartificial intelligence, deep learning, or other computer visiontechniques to detect and track an object across these 2D frames;implement ray casting techniques to estimate distances from the camerato the object projected from a current 2D frame projected onto the 3Dmanifold; calculate a 3D position (i.e., horizontal distance, verticaldistance, and depth) of the object relative to the camera at the timethis 2D frame was recorded based on this ray; and repeat this processfor each subsequent 2D frame recorded by the camera.

In this example, the application can then combine 3D positions of thisobject derived from a set of (e.g., three) consecutive 2D frames in thisvideo feed into one composite position of the object relative to thecamera based on tracked motion of the mobile device over the period oftime that this set of 2D frames was recorded, such as in the form of acomposite 3D bounding box defined relative to the camera and predictedto fully and tightly encompass the object.

In particular, by combining 3D positions of one object derived frommultiple consecutive frames, the application can reject noise andincrease accuracy of the calculated 3D position of the object relativeto the camera over this small set of consecutive 2D frames. However, bylimiting the number of 2D frames in this set, the application canfinalize its calculation of the next position of the object relative tothe camera with limited latency (e.g., at a rate of 8 Hz, or 124milliseconds between consecutive object location calculations, for setsof three consecutive frames recorded by the camera operating at a framerate of 24 Hz).

Additionally, upon calculating a 3D bounding box representing theposition of each object relative to the mobile device (or relative to alocal virtual origin defined relative to the mobile device and definedby the mobile device), the application can then execute a classificationmodel to generate a classification vector (or signature) for eachdetected object, thereby uniquely identifying the object to theapplication.

The application is described below as executing these Blocks of themethod S100 to merge object location estimates from discrete,non-overlapping sets of consecutive 2D frames. However, the applicationcan implement similar methods and techniques for any other number ofoverlapping or non-overlapping sets of consecutive 2D frames recorded bythe camera.

4.1 2D Object Detection and Tracking

As shown in FIG. 1A, while the application is open and active on themobile device, the application can access a stream of 2D frames recordedby a 2D camera in the mobile device in Block S110. The application canthen: implement 2D object detection techniques to detect objects in each2D frame (e.g., via a convolution neural network executed on each 2Dframe); and implement object tracking techniques to link like objectsdetected across this stream of 2D frames and to track objects throughoutthis series of 2D frames.

The application can also leverage object trajectory information derivedfrom preceding frames to predict locations of this object in frames inthe current set and then link objects detected in 2D frames in thepreceding and current sets based on 2D spatial proximity to locationspredicted by this object trajectory at corresponding frame times. Thus,the application can detect objects across multiple 2D frames in order toaccumulate image data about each individual object in order to bettercharacterize and locate each object relative to the mobile device(and/or a local virtual origin defined by the mobile device).

4.2 Mobile Device Motion

As shown in FIG. 1A, while accessing and processing 2D frames recordedby the camera, the application can also track 3D motion of the mobiledevice relative to the earth in Block S112. For example, the applicationcan record accelerations and angular velocities output by accelerometerand gyroscope sensors (e.g., a six-degree-of-freedom IMU), respectively,integrated into the mobile device, and store these timestamped motiondata. The application can also implement dead reckoning techniques toderive translational and rotational changes in the position andorientation of the mobile device between recordation of consecutive 2Dframes. In one implementation, the application (e.g., at the beginningof a recording period for a set of 2D frames) can define a local virtualorigin relative to the mobile device. Therefore, as the mobile devicerecords 2D frames and motion data and detects objects in the area ofinterest, the application can track the current position of the mobiledevice in the area of interest (via the aforementioned inertial trackingand dead-reckoning techniques) and define locations of objects detectedin the area of interest (e.g., and/or a 3D constellation of theseobjects) relative to the local virtual origin.

4.3 Single-Frame Object Volumetric Approximation

As shown in FIGS. 1A, 2, and 3, the application can: implementvisual-inertial odometry, structure from motion, or similar techniquesto derive depth information from a series of 2D frames recorded over aperiod of time and based on motion information (e.g., changes inposition and orientation) of the mobile device tracked over this periodof time; and then construct a 3D manifold or other virtual 3Drepresentation of surfaces in the field of view of the 2D camera.(Alternatively, the application can access similar “loose” 3D perceptioninformation generated and output by an operating system executing on themobile device.)

Upon detecting an object in a first 2D frame—in the set of consecutiveframes recorded by the camera—the application can: calculate a 2Dbounding box around this object in the first 2D frame; and project the2D bounding box and the object depicted in two dimensions in the first2D frame onto the 3D manifold generated from preceding 2D frames andconcurrent motion of the mobile device and defined relative to thecamera. The application can then implement ray casting techniques to:virtually project a first ray from the position of the camera into the2D bounding box projected on the 3D manifold and determine whether thefirst ray intersects the projection of the object onto the 3D manifold.If so, the application can: calculate a distance from the position ofthe camera to a point on the 3D manifold at which the first rayintersects the projection of the object; and store the lateral,longitudinal, and depth positions of this intersection relative to thecamera. The application can repeat this process for many rays cast fromthe location of the camera into the 2D bounding box projected onto the3D manifold.

The application can then populate a 3D graph with a cluster of 3Dpoints—defining lateral, longitudinal, and depth locations relative tothe camera—wherein each point represents an intersection of a ray,virtually cast from the camera, on the object detected in the 2D frameand projected onto the 3D manifold. The application can subsequentlycalculate a 3D bounding box that encompasses this cluster of 3D pointsin the 3D graph and define this 3D bounding box relative to the camera.

The application can repeat this process for this same object detected inthe remaining (e.g., subsequent two) 2D frames in the current set inorder to generate two additional bounding boxes defined relative to thecamera and encompassing a cluster of 3D points representing this object.

4.4 Composite 3D Bounding Box

As shown in FIGS. 1A and 2, the application can then compile theselower-accuracy 3D bounding boxes calculated for the object fromindividual 2D frames—in this designated set of consecutive 2Dframes—into a higher-accuracy 3D location at the object and/or into ahigher-accuracy 3D bounding box tightly containing this object based onabsolute motion of the mobile device between recordation of these 2Dframes.

For example, the application can: access a first 2D frame recorded at afirst time; detect and calculate a first 3D bounding box around a firstobject in the first 2D frame; access a second 2D frame recorded at asecond time; detect and calculate a second 3D bounding box around thefirst object in the second 2D frame; access a third 2D frame recorded ata third time; and detect and calculate a third 3D bounding box aroundthe first object in the third 2D frame. The application can also:calculate a first change in position of the mobile device from a firsttimestamp of the first 2D frame and a second timestamp of the second 2Dframe; and calculate a second change in position of the mobile devicefrom the second timestamp to a third timestamp of the third 2D frame.The application can then: locate the first 3D bounding box within the 3Dgraph with an origin of the 3D graph located at or relative to thelocation and orientation of the mobile device at the first timestamp;locate the second 3D bounding box within the 3D graph based on the firstchange in position of the mobile device; and locate the third 3Dbounding box within the 3D graph based on a sum of the first change andthe second change in position of the mobile device. Finally, theapplication can calculate a volumetric average of these bounding boxes,a volumetric intersection of these bounding boxes, or any othervolumetric combination of these bounding boxes within the 3D graph tocalculate a composite bounding box characterized by greater accuracy anda greater likelihood of tightly containing the object if projected intothe 3D graph.

The application can therefore combine frame-specific 3D bounding boxesaround the object—derived from 2D frames from the current set of 2Dframes—into one composite 3D bounding box.

In this implementation, the application can also: calculate a precedingchange in position of the mobile device from the first timestamp of thefirst 2D frame in this set and a timestamp associated with a preceding3D composite bounding box; and locate a preceding composite 3D boundingbox calculated from the preceding set of 2D frames within the 3D graphbased on the preceding change in position of the mobile device. Theapplication can then calculate the composite 3D bounding box based onthe first, second, and third bounding boxes and the preceding composite3D bounding box, such as with the latter assigned a lower weight.

Alternatively, the application can implement similar methods andtechniques: to locate 3D point clouds associated with a particularobject—derived from individual frames in the current set—into the 3Dgraph based on estimated changes in position and orientation of thecamera over a period of time that the corresponding 2D frames wererecorded; and to then calculate and store a 3D composite bounding boxthat encompasses this aggregated set of 3D points.

In Block S120, the application can generate 3D graphs for each objectdetected in a set of 2D frames and perform the above steps for eachdetected object to generate a 3D constellation of objects around themobile device. More specifically, for each object in a 3D constellationof objects, the application can: for each frame in a subset of theseries of frames: detect the object in the frame and generate a set ofpoints representing estimated distances from a camera of the mobiledevice to surfaces on the object. The application can then: compile theset of points into a cluster of points (i.e. a 3D graph) based on themotion data; and calculate a relative position of the object relative tothe local virtual origin based on the cluster of points. Additionally oralternatively, the application can also calculate a bounding box orrepresentation of the position and/or orientation of the object relativeto the mobile device and/or a local virtual origin defined by the mobiledevice.

4.5 Location Confidence Score

As the application executes the foregoing processes to estimate thelocation of the object—such as in the form of a single 3D pointcontained by the object or in the form of a bounding box around theobject—in subsequent sets of consecutive frames, the application canalso calculate confidence scores for the detected location of theobject.

In one implementation, the application initially outputs a lowconfidence for the presence and location of the object when firstdetected in a 2D frame. However, as the mobile device records additional2D frames and as the application detects and tracks this object acrossthese next 2D frames, and thus amasses data specific for this object,the application can then estimate a trajectory of the object in realspace. For example, the application can: calculate a nominal path of theobject—relative to the camera in the mobile device—from centroids of 3Dcomposite bounding boxes calculated for the object over a series of setsof consecutive 2D frames; implement dead reckoning techniques totransform acceleration and angular velocity data collected by sensors inthe mobile device during recordation of these 2D frames into a path ofthe camera over this period of time; subtract the path of the camerafrom the nominal path of the object to calculate an absolute path of theobject over this period of time; and then extrapolate an absolutetrajectory of the object from this absolute path. (The application canadditionally or alternatively implement visual odometry or othercomputer vision techniques to estimate the trajectory of the object.)

In the foregoing implementation, based on the absolute trajectory of theobject and the change in position and orientation of the camera from thecurrent frame to a next frame (or next set of 2D frames), theapplication can extrapolate a 2D and/or 3D position of the object at thereference time of a next set of consecutive 2D frames recorded by thecamera. Upon detecting the object and calculating its 2D or 3D locationin this next set of 2D frames, the remote computer system can calculatea difference (e.g., a 2D or 3D distance) between the extrapolated andcalculated 2D and/or 3D locations of the object at the current time. Theapplication can then calculate a location confidence score for thecalculated location of the object at this time as a function of (e.g.,proportional to) this difference.

The application can additionally or alternatively calculate a locationconfidence score for the composite 3D location calculated from a currentset of consecutive 2D frames as a function of proportions of 2Dframe-specific bounding boxes—generated from individual frames in thisset of 2D frames—that overlap.

Once the application calculates a location confidence score for presenceand location of the object that exceeds a threshold score (e.g., 40%),the application can: project the 3D bounding box around the objectand/or locate an augmented reality asset (e.g., text, an icon, ananimation) over the object depicted in the next 2D frame recorded by thecamera; and then render this augmented 2D frame on a display of themobile device in substantially real-time. For example, the applicationcan thus selectively render an augmented reality asset on or near anobject only once the application can calculate a location confidencescore exceeding a threshold score in order to limit presentation ofaugmented reality content on or adjacent false-positive objects detectedin these 2D frames.

However, the application can calculate and update the locationconfidence score for the object in any other way.

4.6 Object Characteristics

The application can also classify any detected object in the 3Dconstellation of objects as either static (e.g., “immutable”) or dynamic(e.g., mobile, “mutable”) based on the absolute path of the objectdetected during the recording period of the application. For example,while the application calculates a “null” path for the object, theapplication can label the object as static or immutable. Whilecontinuing to track this object over a subsequent series of 2D frames,the application can label the object as dynamic or mutable once theapplication determines that the absolute path of the object is no longernull, update preceding labels for the object to reflect the object asdynamic or mutable, and preserve this dynamic or mutable label for theobject into the future (and/or for the general object classification orcategory label associated with this object, as described below).

Generally, the application can identify and record other characteristicsof the object, such as the number of detected surfaces of the object,the orientation of the object, the dimensions of the 3D bounding box forthe object, calculated volume of the object, visual patterns present ona surface of the object, or any other characteristics or feature of theobject.

The application can store additional characteristics in association withany object in the 3D constellation of objects, such as: characteristicsof surfaces that define the object (e.g., the number of such surfaces);the structure of the object (e.g., represented as a 3D point cloud) orany other representation of this structure such as the total volume ofthe object; the orientation of the object; the dimensions of a 3Dbounding box of the object; text, symbols, or visual patterns detectedon the object; and/or colors present on the object; etc.

In one implementation, the application can: detect a relative positionof a planar surface as an object in the 3D constellation of objects andstore, in association with this planar surface, a distinct 2D pattern(e.g., stored as an image). Therefore, the application can utilize thedistinct 2D pattern to aid in precisely localizing the mobile devicerelative to a 3D localization map (e.g., by comparing the 2D patternassociated with the object to a 2D pattern associated with an object inthe 3D localization map).

In another implementation, upon classifying an object in the 3Dconstellation of objects, the application can detect the orientation(e.g., pitch, roll, and yaw) of an object in addition to its positionrelative to the mobile device or a local virtual origin defined by themobile device. For example, upon classifying an object as a chair, thesystem can identify the orientation of the chair based on features ofthe chair such as the planar surfaces of the seat and the seatback. Theapplication can detect the orientation of any object for which anorientation can be consistently defined.

4.7 Object Classifier and Object Scores

As shown in FIG. 1A, the application can also implement an objectclassification model—such as in the form of an artificial intelligenceor deep learning model—configured to characterize the object based onlikeness to one or more predefined object classes in Block S130.

In one implementation, the application executes a deep learningclassifier trained to output a likeness score of an object for eachobject class in a prepopulated set of (e.g., 90) unique object classes.For example, the application can pass a region of the current 2D framecontaining a detected object into the deep learning classifier, and thedeep learning classifier can return an “object signature” (i.e. aclassification vector) including an array of scores ordered according toa predefined sequence of class types, wherein each value in the objectsignature represents a degree (or a “ confidence score”) for a likenessbetween the object and a corresponding object class in this prepopulatedset of object classes. In this example, an object signature for theobject can thus include: a highest score that corresponds to a primaryobject class (e.g., one of a cup, a wall, a human, a chair, a table, ashoe, a hat, food, a plant, etc.) most likely to include the object; anda combination of lower scores that correspond to secondary objectclasses and that, in combination, suggest a species or a uniqueness ofthe object.

More specifically, for each object in the 3D constellation of objectsand for each object class in a set of object classes, the applicationcan: calculate a confidence score in the classification vector based onan object classification model and the series of frames, the confidencescore representing likeness of the object to the object class.Therefore, the application can generate an object signature in the formof an array of scores (e.g., contained in a vector). However, theapplication can generate an object signature in any other format.

Thus, the application semantically identifies features in an area ofinterest by identifying “objects” based on the set of 2D frames andmotion data. However, the application does not need to correctlyidentify an object in order to utilize the object in a 3D constellationof objects for the purposes of localization assuming the deep learningclassifier consistently identifies classification vectors for objects inthe area of interest. For this reason, an object in the 3D constellationof objects is not limited to an object from the set of object classes orwhat a human would identify as an object at all. For example, theapplication can detect a sculpture of a turtle and calculate aclassification vector that indicates that the turtle sculpture isprimarily classified as a hat since turtle sculptures may not beincluded in the set of object classes. However, because the applicationcan execute the same deep learning classifier to generate the 3Dlocalization map and the 3D constellation of objects, the applicationwill have identified the turtle sculpture as a hat (with an accompanyingclassification vector or object signature) in the 3D localization mapand therefore the application, upon detecting, the turtle again in a 3Dconstellation of objects can match a newly generated classificationvector for the turtle sculpture to the existing classification vector ofthe turtle sculpture in the 3D localization map. In another example, theapplication may even misidentify a 2D picture or pattern as an object.Although these 2D pictures or patterns may not be considered “objects”according to human perceptions and definitions, the application canstill consistently identify them as objects; generate a classificationvector for these 2D pictures or patterns; and relocalize a mobile devicebased on a 3D constellation of objects including these objects that are,in reality, 2D pictures or patterns.

In one implementation, the application can define an input vector forthe deep learning classifier. The application can generate an inputvector for each object in the 3D classification of objects. The inputvector can include any of the aforementioned object characteristicsdetected in association with the object along with any relevant datarecorded in association with the object—such as regions of 2D framesdepicting the object, a 3D graph depicting the object, etc.

In another implementation, the application can utilize geolocationfiltering to narrow the possible classifications of objects in an area.For example, the mobile device can detect its geolocation (e.g., via GPSor another global navigation system) and compare this geolocation to ageotagged 3D localization map. The application can then identify theclassifications of objects represented in the 3D localization map andconstrain the object classification model to only those objectsrepresented in the 3D localization map corresponding to the mobiledevice's geolocation.

In yet another implementation, the application can execute a generalizedobject classification model and a set of class-specific objectclassification models for each object class evaluated by the generalizedobject classification model. For example, the application can classifyan object as a chair with a high level of confidence and then evaluate achair-specific model to classify the chair as a specific type of chair.

4.8 Object Confidence Score

As shown in FIG. 2, the application can further calculate an objectconfidence score proportional to consistency (e.g., as an inversefunction of variance) or inversely proportional to variance of objectclass scores calculated for an object over a sequence of 2D frames(e.g., in a sequence of classification vectors corresponding to thesequence of 2D frames). For example, the application can: increase anobject confidence score for an object following each consecutive 2Dframe for which the application consistently identifies the object to beof one particular object class; and decrease the object confidence scorefor the object following each consecutive 2D frame for which theapplication determines that the primary object class of the object haschanged.

In another example, in response to recording a 2D frame, the applicationcan calculate scores for correlation of each predefined object class tothe object detected in this 2D frame. For each subsequent 2D frame (orset of consecutive 2D frames), the application can: calculate thevariance in scores for each object class calculated for this object overthese 2D frames; normalize this variance by dividing by a number ofthese consecutive 2D frames; and adjust the object confidence score forthe object as an inverse function of normalized variances for theseobject classes over these number of 2D frames.

In one implementation, the application can weight any classificationsimilarity measure calculated by the application based on the objectconfidence score of each object in the constellation of objects. Forexample, the application can reduce the weight of objects identifiedwith low confidence score when calculating the similarity measure.

However, the application can calculate and update the object confidencescore for the object in any other way.

4.9 Other Objects and the 3D Constellation of Objects

The application can then label the 3D bounding box for the object in the3D graph with a unique object identifier (or “ID”), the objectsignature, the location confidence score, and/or the object confidencescore calculated for the object based on data extracted from the currentset of 2D frames (e.g., the current set of three consecutive 2D frames).(As the application repeats the foregoing process upon receipt of thenext set of 2D frames recorded by the camera and tracks this object overthis set of 2D frames, the application can label the next 3D boundingbox for this object with the same unique object ID, an object signaturecontaining new scores calculated for the same ordered set of objectclasses, a new location confidence score, etc.) The application canimplement this same process for other objects detected in the same setof 2D frames, such as in series or in parallel.

The application can then: initialize a 3D constellation of objects forthe current set of 2D frames; timestamp this 3D constellation ofobjects, such as with a time that the center 2D frame or the last 2Dframe in the current set was recorded; geotag the 3D constellation ofobjects with a GPS location of the mobile device at or near the time ofthe timestamp; and populate the 3D constellation of objects with anindividual 3D point at the centroid of a 3D bounding box containing anobject—such as relative to the camera or to the mobile device moregenerally—for each object in a group of objects detected in this currentset of 2D frames. Additionally or alternatively, for each object in thegroup of objects detected in this current set of 2D frames, theapplication can populate the 3D constellation of objects with 3Dbounding boxes containing each object in this group of objects detectedin the current set of 2D frames.

The application can also transfer unique object IDs, object signatures,outputs of a neural network, location confidence scores, objectconfidence scores, locations or addresses of points representingdiscrete objects, etc. from the 3D graph to corresponding 3D pointsand/or to corresponding 3D bounding boxes in the 3D constellation ofobjects before transmitting the 3D constellation of objects to theremote computer system in (near) real-time via a wireless network.

The application can repeat this process over time to generate one 3Dconstellation of objects near the mobile device per set of consecutive2D frames. For example, for the camera that records 2D frames at a framerate of 24 Hz, the application can: detect objects in sets of threeconsecutive 2D frames recorded by the camera; calculate 3D locations andobject signatures of these objects in each set of three consecutive 2Dframes; compile these derived object data and corresponding uniqueobject identifiers into one 3D constellation of objects of detectedobjects per set of three consecutive 2D frames; and return this 3Dconstellation of objects to the remote computer system at a rate of 8 Hzin Block S140 (e.g., via a local network, the internet or any othermeans).

In one implementation, the system can detect the 3D constellation ofobjects relative to a local virtual origin defined by the mobile device.For example, the mobile device can generate a local virtual origin uponinitiating execution of the application. The mobile device can thentrack its position relative to the local virtual origin and thereforethe position of the 3D constellation of objects relative to the localvirtual origin. Therefore, upon comparing the 3D constellation ofobjects to a 3D localization map, the application can calculate atransform relating the local virtual origin to a global virtual originof the 3D localization map. More specifically, the application can:detect positions of the 3D constellation of objects relative to a localvirtual origin based on the series of frames and the motion data;calculate the transform aligning the local virtual origin with a globalvirtual origin of the 3D localization map; and calculate the position ofthe mobile device relative to the global virtual origin of the 3Dlocalization map.

5. Unique Object Detection

The application and/or the remote computer system can leverage theobject signature of an object detected in a 2D frame to distinguish theobject from other objects detected in this 2D frame or represented in a3D constellation of objects and/or to inform selection and thenrendering of an augmented reality asset linked to the object in a 2Dframe.

In one implementation, the application detects a first and a secondobject in a first 2D frame, implements the object classifier to generateobject signatures representing these objects, and thus distinguishesbetween the first and second objects in this first 2D frame based ondifferences between their object signatures. The application repeatsthis process over subsequent 2D frames and then links a new objectdetected in a later 2D frame to the first object detected in the first2D frame based on similarities between their object signatures (e.g.,based on minor “drift” between scores for all object classes in thepredefined set of classes represented in object signatures for both thefirst and the new objects)—such as in addition to or instead of linkingthe first and new object based on 2D silhouette similarities or byoverlapping trajectories—without necessitating that the objectclassifier be trained to distinguish many (e.g., thousands of) objectgenera and their many (e.g., millions) of species.

In one example, the application detects two objects in a first 2D frameand calculates object signatures for both objects, both of which includehighest scores for a “human” object class but differing scores for other“secondary” object classes. The application repeats this process forsubsequent 2D frames recorded by the camera and distinguishes and tracksthese two unique humans across these subsequent 2D frames based onsimilarities and differences in “secondary” object classes in theirobject signatures.

The remote computer system can similarly leverage the object signatureof an object to distinguish a unique object—represented in a 3D sparsemap received from the mobile device—associated with an augmented realityasset from other unique objects not associated with augmented realityassets for the space currently occupied by the mobile device (and for abrand associated with the application, or for an experience hosted bythe application, etc.) In one implementation, the remote computersystem: extracts both a class or “genus” of an object (e.g., that theobject is a cup) and a lower-level “species” of the object (e.g., thatthe object is a coffee cup branded with a logo of a particular coffeeshop) from object scores contained in the object signature of theobject; and then verifies a link between this object and an augmentedreality asset associated with this space based on both the genus and thespecies of the object.

For example, the remote computer system can determine that an object isof a particular known object genus based on the object class associatedwith the highest score in the object signature. The remote computersystem can also determine that the object is of a particular lower-level“species” (e.g., that the object is a coffee cup branded with a logo ofa particular coffee shop) based on a similarity between: scores ofmultiple object classes in the object signature; and a preloadeddefinition of this species represented by a combination of specificscores or score ranges for these object classes. The remote computersystem can then return an augmented reality asset to the mobile deviceif available for this species and genus of object in this spacecurrently occupied by the mobile device.

The application can then implement similar methods and techniques toidentify an object in a 2D frame and to verify whether an augmentedreality asset received from the remote computer system corresponds tothis object. In one example, when the mobile device is present at acoffee shop, the app: identifies a first coffee cup branded with a logoof the coffee shop in a sequence of 2D frames; projects augmentedreality assets supplied by this coffee shop over the first coffee cup inthis sequence of 2D frames; and renders these augmented frames on thedisplay of the mobile device. However, when the application identifies asecond water glass or a second cup branded with a different logo in thissequence of 2D frames, the application can: refrain from rendering thisaugmented reality asset over the second coffee cup in this sequence of2D frames; or project a different augmented reality asset over thesecond coffee cup in this sequence of 2D frames.

6. Localization

As shown in FIG. 1A and in FIG. 4, in Block S150, upon receipt of a 3Dconstellation of objects at a remote computer system, wherein the 3Dconstellation of objects can include the position of each objectdetected at the mobile device and the classification of each object, theremote computer system can compare the 3D constellation of objects tocorpuses of 3D localization maps (or to one global 3D localization map)in order to quickly localize the mobile device without necessitatingtransfer of such a (large) 3D localization map to the mobile device andwithout necessitating additional, expensive computations to compare a 3Dconstellation of objects to this 3D localization map at the mobiledevice. In particular, the remote computer system can leverage a sparse,lightweight 3D map (e.g., the 3D constellation of objects) received fromthe mobile device in order to: quickly localize the mobile device and toaccess augmented reality assets assigned to static and/or dynamicobjects proximal to the mobile device's location; enable the mobiledevice to allocate its computational power to detecting and classifyingobjects in the field of view of its camera, projecting augmented realityassets onto 2D frames recorded by the camera, and then rendering thisaugmented 2D frame on its display.

In one implementation, the remote computer system: receives, in BlockS140, a timestamped, geotagged, 3D constellation of objects generated bythe mobile device; reads a geotag from the 3D constellation of objects;and retrieves a 3D localization map of a space associated with ageospatial location nearest a geospatial location specified in thegeotag. The remote computer system can then, in Block S150, calculate aparticular position and orientation of the mobile device—relative to thevirtual origin in the 3D localization map—that minimizes distancesbetween: points representing objects of particular objects classes inthe 3D constellation of objects; and locations of objects of the sameclasses depicted in the 3D localization map of the space. In particular,the 3D constellation of objects can depict 3D locations of objects inthe field of view of the camera in the mobile device and relative to thecamera over a brief (e.g., ˜125-millisecond) period of time. The remotecomputer system can thus calculate a translation and a rotation in threedimensions that transforms the 3D constellation of objects (definedaround a local virtual origin of the 3D constellation of objects) to aposition and orientation in the space that minimizes distances betweeneach object position in the 3D constellation of objects detected duringthe recording period at the mobile device; and a set of objects of likeobject classes (e.g., characterized by the same primary object class orsimilar object signatures) in the 3D localization map. The applicationcan thus transform an approximate position and orientation of the mobiledevice relative to the local virtual origin (and, therefore, the 3Dconstellation of objects) to a location of the mobile device relative tothe 3D localization map at the end of the recording period of the mobiledevice by applying the same transform to the nominal location of themobile device. For example, the remote computer system can implementparticle filter techniques to generate a set of particles representingpossible positions and orientations of the camera around the location ofthe geotag during this brief period of time and to then test theseparticles for minimum distances between objects depicted in the 3Dconstellation of objects and objects of the same class depicted in the3D localization map, such as in series or in parallel until a particlematching more than a threshold number of objects and with less than athreshold error between the 3D constellation of objects and the 3Dlocalization map is identified.

In one implementation, the application can first calculate a maximumgeometric similarity measure between the 3D constellation of objects andthe 3D localization map (e.g., for each transformation tested by theapp) by comparing the configuration of objects in 3D space in the 3Dconstellation of objects to the configuration of the objects in the 3Dlocalization map (e.g., for example by calculating a Euclidian distancebetween objects in the 3D constellation of objects and the 3Dlocalization map). In response to the application calculating ageometric similarity measure greater than a predetermined thresholdgeometric similarity measure, the application can then evaluate whethereach object is classified in a similar manner to the nearest object inthe 3D localization map by calculating a classification similaritymeasure (e.g., between a classification vector of an object in the 3Dconstellation of objects and a corresponding object in the 3Dlocalization map). In response to calculating a classificationsimilarity measure greater than a predetermined threshold classificationsimilarity measure, the application can return the transformation forwhich these similarity measures were calculated.

More specifically, the application can: calculate a geometric similaritymeasure between the 3D constellation of objects and the 3D localizationmap. Subsequently, the application can, in response to the geometricsimilarity measure exceeding a geometric similarity threshold: identifya mapping of a set objects in the 3D constellation of objects to acorresponding set of objects in the 3D localization map; identify aclassification similarity measure between classification vectors of theset of objects in the 3D constellation of objects and classificationvectors of the corresponding set of objects in the 3D localization mapbased on the mapping; and, in response to the classification similaritymeasure exceeding a classification similarity threshold, calculate thetransform aligning the 3D constellation of objects with the 3Dlocalization map.

In this implementation, the remote computer system can also: filter the3D constellation of objects to include objects tagged as static orimmutable only and compare this filtered 3D constellation of objects tothe 3D localization map to determine the position and orientation of themobile device; or selectively match static or immutable objectsrepresented in the 3D constellation of objects only to like static orimmutable objects represented in the 3D localization map. Similarly, theremote computer system can filter the 3D constellation of objects toinclude objects tagged with object confidence scores that exceed apreset threshold. The remote computer system can additionally oralternatively weight objects in the 3D constellation of objects as afunction of whether these objects are determined to be static.

Furthermore, in the variation described above in which the applicationincorporates a 3D bounding box for each object represented in the 3Dconstellation of objects, the remote computer system can compare thesize of a bounding box representing a particular object depicted in the3D constellation of objects to a size of a bounding box representing anobject of a like class depicted in the 3D localization map in order: toinform initial comparison of the 3D constellation of objects and the 3Dlocalization map; to verify correlation of objects of like objectclasses between the 3D constellation of objects and the 3D experiencebased on like object size; or to isolate a particular position andorientation of the mobile device from a set of possible positions andorientations derived from the object location/object class comparisondescribed above.

The remote computer system can then return the location and orientationof the mobile device—such as relative to the virtual origin in the 3Dlocalization map—to the mobile device. For example, the remote computersystem can return to the mobile device a transform that represents atranslation and rotation offset between the virtual origin in the 3Dlocalization map and the real position and orientation of the mobiledevice at approximately the current time. The application—currentlyexecuting on the mobile device—can then project assembly media, definedfor the space relative to the virtual origin, onto subsequent 2D framesin (near) real-time based on this transform. In particular, theapplication can merge augmented reality assets spatially referenced to avirtual origin and the transform to spatially locate the augmentedreality assets on 2D frames recorded by the camera and rendered on thedisplay of the mobile device in (near) real-time.

The remote computer system can repeat this process upon receipt of anext 3D constellation of objects from the mobile device, such asincluding prioritizing testing of possible positions and orientations ofthe mobile device near the last position and orientation calculated forthe mobile device or prioritizing testing of objects detected or datagenerated near the current location of the mobile device.

The remote computer system can also implement a first process to rapidlyachieve an initial location estimate of the mobile device. Afterderiving this initial location estimate of the mobile device, the remotecomputer system can execute a second process according to the foregoingmethods and techniques to refine the calculated location and orientationof the mobile device. The remote computer system can thereforeselectively implement a process tailored for speed to calculate aninitial location estimate of the mobile device and then implement aprocess tailored for accuracy to refine the initial location of themobile device estimate over time. Furthermore, to refine the initiallocation estimate of the mobile device, the remote computer system can:execute multiple processes simultaneously to refine the initial locationestimate; then compare results of these processes according to a singlemetric (e.g., how well the detected objects and planes are aligned by aresult) to determine which of these results is most likely to be mostaccurate; and then refine the location estimate according to this oneresult (or based on a weighted or non-linear combination of theseresults).

In one implementation, the application can calculate a transformationpositionally matching a 3D constellation of objects (defined about alocal virtual origin) to a 3D localization map defined about a globalvirtual origin. The application can then calculate a position of themobile device relative to the global virtual origin by translatingand/or rotating the last-calculated position of the mobile devicerelative to the local virtual origin by the transform. However, thelast-calculated position of the mobile-device recorded during a firstrecording period may be out of date at the time when the applicationcalculates the transform. In this case, the mobile device can record asecond series of frames and a second set of motion data in order toupdate its location relative to the 3D constellation of objects. Theapplication can then transform the newly calculated location (and/ororientation) of the mobile device relative to the 3D constellation ofobjects to a location (and/or orientation) of the mobile device relativeto the 3D localization map. More specifically, the mobile device can,during a second recording period, succeeding reception of the transformat the mobile device: record a second series of frames; and record asecond set of motion data. The mobile device can additionally calculatethe position of the mobile device relative to the 3D localization mapbased on the transform, the second series of frames, and the second setof motion data.

Furthermore, the mobile device can continuously track its position usingaforementioned inertial tracking and/or dead reckoning techniques. Morespecifically, the mobile device can calculate its position by: trackinga position of the mobile device relative to the first 3D constellationof objects based on the second set of frames and the second set ofmotion data; and, in response to receiving the transform from the remotecomputer system, transforming the position of the mobile device relativeto the first 3D constellation of objects to the position of the mobiledevice relative to the 3D localization map based on the transform.

In one implementation, the mobile device can: detect a second 3Dconstellation of objects; classify these objects; and align theseobjects with the localization map in order to calculate an updatedposition. In this implementation, upon losing sight of the previous 3Dconstellation of objects, the mobile device can record a second seriesof frames and a second set of motion data in order to detect a second 3Dconstellation of objects. The application can utilize the relativepositions of shared objects between the first 3D constellation ofobjects and the second 3D constellation of objects to obtain an initial(rough) estimate of the position of the mobile device relative to the 3Dlocalization map. Alternatively, the application can perform theabove-described localization techniques to calculate the position of themobile device relative to the 3D localization map. More specifically theapplication can: detect relative positions of a second 3D constellationof objects based on the second series of frames and the second set ofmotion data; generate classifications of the second 3D constellation ofobjects by calculating a classification of each object in the second 3Dconstellation of objects based on the second series of frames; andcalculate the position of the mobile device by matching the second 3Dconstellation of objects to a subset of objects in the 3D localizationmap.

7. Augmented Reality Content Creation

In one implementation, the remote computer system can interface with acontent creation app executed at a content creation device, which canpopulate a 3D localization map including objects in an area of interest(e.g., that has been mapped by an operator using the operatorapplication). More specifically, the content creation app can, at acontent creation device: render a representation of the 3D localizationmap; render a content creation interface; and receive input at thecontent creation interface representing locations of augmented realityassets in the 3D localization map. In response to the input at thecontent creation interface, the application can then create theaugmented reality assets in the 3D localization map according to theinput at the content creation interface.

However, the application can generate augmented reality assets in anyother way.

8. Augmented Reality Assets

As shown in FIGS. 2 and 3, if the remote computer system returns anaugmented reality asset linked to an asset detected by the applicationin a current or last frame recorded by the camera, the application canthen verify that rules for rendering this augmented reality asset aremet and then project this augmented reality asset into the viewfinder onthe mobile device accordingly in Block S160.

In one implementation, the remote computer system returns augmentedreality assets for the space occupied by the mobile device to the mobiledevice. For example, the remote computer system can return to the mobiledevice augmented reality assets linked to fixed or immutable objects inthe space (e.g., walls, tables, fixed art installations, trees) near(i.e. proximal to) the location of the mobile device and/or within ornear the field of view of the camera in the mobile device predicted bythe remote computer system based on the mobile device's location and/ororientation; the application can then cache these augmented realityassets and selectively overlay them over or adjacent correspondingstatic or immutable objects detected by the application in 2D framessubsequently recorded by the camera. The remote computer system can alsoreturn to the mobile device: augmented reality assets linked to dynamicand immutable (or “mobile”) objects represented directly in the current3D constellation of objects received from the mobile device; and/oraugmented reality assets linked to dynamic or immutable objectspredicted to occupy the space with the mobile device, regardless ofwhether the application has yet detected these objects.

Additionally, the remote computer system can return and the mobiledevice can render other types of augmented reality assets uponlocalization of the mobile device relative to a 3D localization map.Thus, augmented reality assets can include data pertaining to thelocation of the user but not tied to a particular location itself. Forexample, if the mobile device is located within a particular room in astore, the remote computer system can return and the mobile device canrender a list of products available in the room of the store, withoutthis list appearing as in augmented reality as an object (e.g., theapplication can render the list in an adjacent interface). Additionally,augmented reality assets can include data pertaining to the location ofother mobile devices relative to the 3D localization map. For example,the remote computer system can return and the mobile device can renderthe location of other mobile devices relative to the mobile device andindicate the distance between the mobile device an another mobile devicein the application executing on the mobile device.

Therefore, in one implementation, the application can: calculate aposition of the mobile device relative to the 3D localization map and anorientation of the mobile device relative to the 3D localization map;and identify a subset of augmented reality assets in the set ofaugmented reality assets within a field of view of the mobile devicebased on the position of the mobile device relative to the 3Dlocalization map and the orientation of the mobile device relative tothe 3D localization map; and render the subset of augmented realityassets onto a display based on positions of the subset of augmentedreality assets in the 3D localization map and based on the position ofthe mobile device relative to the 3D localization map and theorientation of the mobile device relative to the 3D localization map.

In one implementation, the application can initiate download and cachingof augmented reality assets before localization of the mobile device iscompleted at the remote computer system. For example, the mobile devicecan detect its geolocation or other rough positional estimate and theapplication can compare this geolocation to geolocations of known 3Dlocalization maps and identify augmented reality assets proximal to theestimated position of the mobile device. Therefore, the application canconcurrently begin caching and synchronizing augmented reality assetsand localizing the mobile device. More specifically, the applicationcan: estimate an approximate position of the mobile device relative tothe 3D localization map; and identify the set of augmented realityassets defined in the 3D localization map proximal to the approximateposition.

The mobile device then: caches these augmented reality assets receivedfrom the remote computer system; selectively projects (e.g., “overlays”)these assets on 2D frames recorded by the camera based on signatures ofobjects detected in the frames, whether these objects are immutable ormutable, rules for rendering these augmented reality assets, and thetransform representing the position and orientation of the mobile deviceat approximately this time; and then renders these 2D frames withaugmented content on the display of the mobile device. For example, eachaugmented reality asset can be spatially referenced to the virtualorigin defined in the 3D localization map. Upon receipt of a next 2Dframe reordered by the camera, the application can: implement methodsand techniques described above to identify an object linked to aparticular augmented reality asset stored in the cache; calculate a 3Dposition of the object relative to the mobile device (e.g., relative tothe optical axis and optical sensor of the camera); match the particularobject to a particular augmented reality asset stored in the cache; andthen verify that the particular object fulfills rules designated forthis particular augmented reality asset. If so, the application canthen: combine the position of the particular object relative to themobile device with the last transform received from the remote computersystem and representing a last calculated position and orientation ofthe mobile device relative to the virtual origin to derive an objecttransform representing the position and orientation of the particularobject relative to the virtual origin; and project the particularaugmented reality asset onto the current 2D frame based on the objecttransform.

Furthermore, for a dynamic and mutable object detected in this 2D frameand associated with an augmented reality asset, the application canproject this augmented reality asset onto this 2D frame based on theposition of this object relative to the camera calculated by theapplication. The application can repeat these processes for otherimmutable and mutable objects detected in this 2D frame before renderingthis augmented 2D frame on the mobile device's display substantially inreal-time.

In one implementation, the application can generate an occlusion maskfor the mobile device for use in rendering augmented reality assets thatmay be partially obscured by other objects in the scene. For example, inimplementations that include a composite 3D map (i.e. a 3D point cloudmap in addition to the set of objects in the 3D localization map), theapplication can calculate the field of view of the mobile device in thecomposite 3D map (e.g., based on camera characteristics of the mobiledevice and the position and orientation of the mobile device relative tothe composite 3D map). The application can then identify surfaces and/orobjects obscuring an augmented reality asset and, from the perspectiveof the mobile device, generate an occlusion mask representing regions ofthe field of view of the mobile device occupied by objects or surfacesthat occlude the augmented reality asset. More specifically, theapplication can: calculate a field of view of the mobile device in thecomposite 3D map based on the position of the mobile device relative tothe 3D localization map; identify an augmented reality asset in the setof augmented reality assets within the field of view of the mobiledevice in the composite 3D map; generate an occlusion mask for theaugmented reality asset based on the field of view of the mobile devicein the composite 3D map; and render the augmented reality asset obscuredby the occlusion map onto the display of the mobile device.

In one implementation, the mobile device can render augmented realityassets as an overlay over a real object in the area of interest. Forexample, the mobile device can augment the color, surface texture, orany other superficial feature of existing objects in the area ofinterest. In rendering an overlay object, the mobile device can utilizean object specific model to identify the location of features of theobject in order to locate an augmented reality overlay on the screen ofthe device such that the augmented reality overlay aligns with the realobject in the area of interest. More specifically, the application can,during a second recording period succeeding the first recording period:record a second series of frames; and record a second set of motiondata. The application can then: detect an augmented object within thefield of view of the mobile device based on the second series of frames;calculate a position of the augmented object based on the second seriesof frames and the second set of motion data; calculate a signature ofthe augmented object based on the second series of frames and the secondset of motion data; and, in response to matching the signature of theaugmented object to a signature of an object represented in the 3Dlocalization map corresponding to an overlay in the set of augmentedreality assets based on the position of the augmented object, render anoverlay on the augmented object on the display.

As described above, the application can continue to access 2D framesrecorded by the camera, transform these 2D frames into 3D constellationof objects, and return these 3D constellation of objects to the remotecomputer system; and the remote computer system can continue to localizethe mobile device based on the 3D constellation of objects, return thelocation of the mobile device to the mobile device (e.g., in the form ofa transform between the virtual origin and the calculated position andorientation of the mobile device), and return augmented reality assetsand related rules to the mobile device as the mobile device nears orenters positions and orientations associated with these augmentedreality assets. Upon receipt of additional augmented reality assets andlocations of the mobile device, the application can store theseadditional augmented reality assets in the cache and selectively projectaugmented reality assets from the cache onto subsequent 2D framesrecorded by the camera. Therefore, at the mobile device and during asecond recording period succeeding the first recording period, theapplication can: record a second series of frames; and record a secondset of motion data. The application can then: calculate a position andorientation of the mobile device relative to the 3D localization mapbased on the second series of frames and the second set of motion data;project a field of view of the mobile device in the 3D localization mapbased on the position and orientation of the mobile device relative tothe 3D localization map; identify an augmented reality asset in the setof augmented reality assets within the field of view of the mobiledevice; and render the augmented reality asset on the display of themobile device based on the position of the augmented reality assetrelative to the 3D localization map and the position and orientation ofthe mobile device relative to the 3D localization map.

9. Variations

In one variation, rather than return a transform or other representationof the mobile device's location relative to a virtual origin defined inthe 3D localization map, the remote computer system can insteadcalculate a geospatial location and orientation of the mobile device andreturn these geospatial values to the mobile device. The remote computersystem can also locate augmented reality assets within a geospatialcoordinate system rather than relative to the virtual origin.

In another variation, the application can implement methods andtechniques similar to those described above: to detect surfaces, such aswalls, floors, ceilings, table tops; to calculate surface signatures forthese surfaces; and to represent these surfaces within a 3Dconstellation of objects. The remote computer system can then implementmethods and techniques similar to those described above to localize themobile device based on surfaces represented in a 3D constellation ofobjects and like surfaces represented in the 3D localization map.

In yet another variation, the application can implement methods andtechniques similar to those described above to generate 2D or 3Daugmented reality overlay frames containing augmented reality assetsonly and then render these overlay frames on an augmented realityheadset (e.g., augmented reality glasses) worn by a user, therebyrendering these augmented reality assets within the user's vision andsubstantially aligned to corresponding objects in the field around theuser. For example, upon receipt of a next 2D frame reordered by thecamera, the application can: implement methods and techniques describedabove to identify an object linked to a particular augmented realityasset stored in the cache; calculate a 3D position of the objectrelative to the mobile device (e.g., relative to the optical axis andoptical sensor of the camera); match the particular object to aparticular augmented reality asset stored in the cache; and then verifythat the particular object fulfills rules designated for this particularaugmented reality asset. If so, the application can then: combine theposition of the particular object relative to the mobile device with thelast transform received from the remote computer system and representinga last calculated position and orientation of the mobile device relativeto the virtual origin to derive an object transform representing theposition and orientation of the particular object relative to thevirtual origin; and project the particular augmented reality asset ontoan empty 2D image based on the object transform. The application canrepeat this process for other objects detected in the 2D frame beforerendering this 2D image on the mobile device's display substantially inreal-time.

In another variation, once the location confidence score and the objectconfidence score for a static or immutable object—detected by app andreceived by the remote computer system—exceed corresponding thresholdscores, the remote computer system can inject location and objectsignature data for this object into the 3D localization map in order toextend the 3D localization map with representations of additionalobjects and/or to supplement existing representations of objects in the3D localization map with additional data. Similarly, as the remotecomputer system collects data from mobile devices moving throughlocations associated with discrete 3D localization maps and extendsthese 3D localization maps, the remote computer system can stitch this3D localization maps together to generate a larger, more comprehensive“global” localization map.

The systems and methods described herein can be embodied and/orimplemented at least in part as a machine configured to receive acomputer-readable medium storing computer-readable instructions. Theinstructions can be executed by computer-executable componentsintegrated with the application, applet, host, server, network, website,communication service, communication interface,hardware/firmware/software elements of a user computer or mobile device,wristband, smartphone, or any suitable combination thereof. Othersystems and methods of the embodiment can be embodied and/or implementedat least in part as a machine configured to receive a computer-readablemedium storing computer-readable instructions. The instructions can beexecuted by computer-executable components integrated bycomputer-executable components integrated with apparatuses and networksof the type described above. The computer-readable medium can be storedon any suitable computer readable media such as RAMs, ROMs, flashmemory, EEPROMs, optical devices (CD or DVD), hard drives, floppydrives, or any suitable device. The computer-executable component can bea processor but any suitable dedicated hardware device can(alternatively or additionally) execute the instructions.

As a person skilled in the art will recognize from the previous detaileddescription and from the figures and claims, modifications and changescan be made to the embodiments of the invention without departing fromthe scope of this invention as defined in the following claims.

I claim:
 1. A method for rendering augmented reality content comprising:at a mobile device: during a recording period: recording a series offrames; and recording motion data representing motion of the mobiledevice; detecting relative positions of a 3D constellation of objectsbased on the series of frames and the motion data; generating a set ofclassification vectors of the 3D constellation of objects by calculatinga classification vector for each object in the 3D constellation ofobjects, the classification vector representing a confidence score ofthe object for each object class in a set of object classes; andreturning the 3D constellation of objects and the set of classificationvectors to a remote computer system; at the remote computer system:calculating a transform aligning the 3D constellation of objects with a3D localization map defining a set of objects characterized by relativepositions and classification vectors matching the relative positions andthe set of classification vectors of the 3D constellation of objects;and returning, to the mobile device, a set of augmented reality assetsdefined by the 3D localization map and the transform; and at the mobiledevice, rendering the set of augmented reality assets onto a displaybased on positions of the set of augmented reality assets in the 3Dlocalization map and based on the transform.
 2. The method of claim 1,wherein detecting the relative positions of the 3D constellation ofobjects based on the series of frames and the motion data furthercomprises, for each object in the 3D constellation of objects: for eachframe in a subset of the series of frames: detecting the object in theframe; and generating a set of points representing estimated distancesfrom a camera of the mobile device to surfaces on the first object;compiling the set of points into a cluster of points based on the motiondata; and calculating a relative position of the object relative to thelocal virtual origin based on the cluster of points.
 3. The method ofclaim 1, wherein calculating a classification vector for each object inthe 3D constellation of objects further comprises, for each object inthe 3D constellation of objects and for each object class in a set ofobject classes, calculating a confidence score in the classificationvector based on an object classification model and the series of frames,the confidence score representing likeness of the object to the objectclass.
 4. The method of claim 1, wherein calculating the transformaligning the 3D constellation of objects with a 3D localization mapfurther comprises: calculating a geometric similarity measure betweenthe 3D constellation of objects and the 3D localization map; and inresponse to the geometric similarity measure exceeding a geometricsimilarity threshold: identifying a mapping of a set objects in the 3Dconstellation of objects to a corresponding set of objects in the 3Dlocalization map; calculating a classification similarity measurebetween classification vectors of the set of objects in the 3Dconstellation of objects and classification vectors of the correspondingset of objects in the 3D localization map based on the mapping; and inresponse to the classification similarity measure exceeding aclassification similarity threshold, calculating the transform aligningthe 3D constellation of objects with the 3D localization map.
 5. Amethod for rendering augmented reality content comprising: at a mobiledevice: during a first recording period: recording a first series offrames; and recording a first set of motion data representing motion ofthe mobile device; detecting relative positions of a first 3Dconstellation of objects based on the first series of frames and thefirst set of motion data; calculating a classification vector of eachobject in the first 3D constellation of objects based on the firstseries of frames; and returning the first 3D constellation of objectsand the classification vector of each object to a remote computersystem; at the remote computer system: calculating a transform aligningthe first 3D constellation of objects with a 3D localization mapdefining a set of objects characterized by relative positions andclassification vectors matching the relative positions and theclassification vectors of the first 3D constellation of objects; andreturning, to the mobile device: a set of augmented reality assetsdefined by the 3D localization map; and the transform; and at the mobiledevice: calculating a position of the mobile device relative to the 3Dlocalization map based on the transform; and rendering the set ofaugmented reality assets onto a display based on positions of the set ofaugmented reality assets in the 3D localization map and based on theposition of the mobile device in the 3D localization map.
 6. The methodof claim 5: further comprising, at the mobile device during a secondrecording period, succeeding reception of the transform at the mobiledevice: recording a second series of frames; and recording a second setof motion data; and wherein, at the mobile device, calculating theposition of the mobile device relative to the 3D localization mapfurther comprises calculating the position of the mobile device relativeto the 3D localization map based on the transform, the second series offrames, and the second set of motion data.
 7. The method of claim 6,wherein calculating the position of the mobile device relative to the 3Dlocalization map based on the transform, the second series of frames,and the second set of motion data further comprises: tracking a positionof the mobile device relative to the first 3D constellation of objectsbased on the second set of frames and the second set of motion data; andin response to receiving the transform from the remote computer system,transforming the position of the mobile device relative to the first 3Dconstellation of objects to the position of the mobile device relativeto the 3D localization map based on the transform.
 8. The method ofclaim 6, wherein calculating the position of the mobile device relativeto the 3D localization map based on the transform, the second series offrames, and the second set of motion data further comprises: detectingrelative positions of a second 3D constellation of objects based on thesecond series of frames and the second set of motion data; generatingclassification vectors of the second 3D constellation of objects bycalculating a classification vector of each object in the second 3Dconstellation of objects based on the second series of frames; andcalculating the position of the mobile device by matching the second 3Dconstellation of objects to a subset of objects in the 3D localizationmap.
 9. The method of claim 5: wherein calculating the position of themobile device relative to the 3D localization map further comprisescalculating the position of the mobile device relative to the 3Dlocalization map and an orientation of the mobile device relative to the3D localization map; and wherein rendering the set of augmented realityassets onto a display further comprises: identifying a subset ofaugmented reality assets in the set of augmented reality assets within afield of view of the mobile device based on the position of the mobiledevice relative to the 3D localization map and the orientation of themobile device relative to the 3D localization map; and rendering thesubset of augmented reality assets onto a display based on positions ofthe subset of augmented reality assets in the 3D localization map andbased on the position of the mobile device relative to the 3Dlocalization map and the orientation of the mobile device relative tothe 3D localization map.
 10. The method of claim 5, wherein returning,to the mobile device, the set of augmented reality assets defined by the3D localization map further comprises: estimating an approximateposition of the mobile device relative to the 3D localization map; andidentifying the set of augmented reality assets defined in the 3Dlocalization map proximal to the approximate position.
 5. method ofclaim 5, further comprising: at a mapping device: recording a secondseries of frames capturing an area of interest; and recording a secondset of motion data representing motion of the mapping device; andreturning the second series of frames and the second set of motion datato the remote computer system; at the remote computer system:identifying a set of objects based on the second series of frames andthe second set of motion data; for each object in the set of objects:calculating a location of the object relative to a virtual origin; andcalculating a classification vector of the object; and generating the 3Dlocalization map based on the location of each object in the set ofobjects relative to the virtual origin and the classification vector ofeach object in the set of objects.
 12. The method of claim 11, furthercomprising: generating a sparse set of points representing distancesfrom a camera of the mapping device to surfaces of the area of interestbased on the second set of frames and the second set of motion data;generating a sparse 3D point cloud reconstruction of the area ofinterest based on the sparse set of points; and at the mapping device,rendering the sparse point cloud 3D reconstruction of the area ofinterest.
 13. The method of claim 12, further comprising: at the remotecomputer system: generating a dense set of points representing distancesfrom the camera of the mapping device to surfaces of the area ofinterest based on the second set of frames and the second set of motiondata; generating a dense 3D point cloud reconstruction of the area ofinterest based on the dense set of points; and overlaying the dense 3Dpoint cloud reconstruction over the 3D localization map to generate acomposite 3D map.
 14. The method of claim 13, wherein rendering the setof augmented reality assets onto a display further comprises, at themobile device: calculating a field of view of the mobile device in thecomposite 3D map based on the position of the mobile device relative tothe 3D localization map; identifying an augmented reality asset in theset of augmented reality assets within the field of view of the mobiledevice in the composite 3D map; generating an occlusion mask for theaugmented reality asset based on the field of view of the mobile devicein the composite 3D map; and rendering the augmented reality assetobscured by the occlusion map onto the display.
 15. The method of claim11, further comprising: at a content creation device: rendering arepresentation of the 3D localization map; rendering a content creationinterface; and receiving input at the content creation interfacerepresenting locations of augmented reality assets in the 3Dlocalization map; and creating the augmented reality assets in the 3Dlocalization map according to the input at the content creationinterface.
 16. A method for rendering augmented reality contentcomprising: at a mobile device, during a first recording period:recording a first series of frames; and recording a first set of motiondata representing motion of the mobile device; detecting relativepositions of a 3D constellation of objects based on the first series offrames and the first set of motion data; generating classificationvectors of the 3D constellation of objects by, for each object in the 3Dconstellation of objects, calculating a confidence score of the objectfor each object class in a set of object classes; calculating atransform aligning the 3D constellation of objects with a 3Dlocalization map defining a set of objects characterized by relativepositions and classification vectors matching the relative positions andthe classification vectors of the 3D constellation of objects; accessinga set of augmented reality assets defined by the 3D localization map andthe transform; calculating a position of the mobile device relative tothe 3D localization map based on the transform and the first set ofmotion data; and rendering the set of augmented reality assets onto adisplay based on positions of the set of augmented reality assets in the3D localization map and based on the position of the mobile device inthe 3D localization map.
 17. The method of claim 16, wherein renderingthe set of augmented reality assets onto a display further comprises:during a second recording period, succeeding the first recording period:recording a second series of frames; and recording a second set ofmotion data; detecting an augmented object within the field of view ofthe mobile device based on the second series of frames; calculating aposition of the augmented object based on the second series of framesand the second set of motion data; calculating a signature of theaugmented object based on the second series of frames and the second setof motion data; and in response to matching the signature of theaugmented object to a signature of an object represented in the 3Dlocalization map corresponding to an overlay in the set of augmentedreality assets based on the position of the augmented object, renderingan overlay on the augmented object on the display.
 18. The method ofclaim 16, wherein rendering the set of augmented reality assets onto adisplay further comprises: at the mobile device, during a secondrecording period succeeding the first recording period: recording asecond series of frames; and recording a second set of motion data;calculating a position and orientation of the mobile device relative tothe 3D localization map based on the second series of frames and thesecond set of motion data; projecting a field of view of the mobiledevice in the 3D localization map based on the position and orientationof the mobile device relative to the 3D localization map; identifying anaugmented reality asset in the set of augmented reality assets withinthe field of view of the mobile device; and rendering the augmentedreality asset on the display of the mobile device based on the positionof the augmented reality asset relative to the 3D localization map andthe position and orientation of the mobile device relative to the 3Dlocalization map.
 19. The method of claim 16: wherein detecting therelative positions of the 3D constellation of objects further comprises,detecting positions of the 3D constellation of objects relative to alocal virtual origin based on the series of frames and the motion data;wherein calculating the transform aligning the 3D constellation ofobjects with a 3D localization map further comprises calculating thetransform aligning the local virtual origin with a global virtual originof the 3D localization map; and wherein calculating the position of themobile device relative to the 3D localization map further comprisescalculating the position of the mobile device relative to the globalvirtual origin of the 3D localization map.
 20. The method claim 16,wherein detecting the relative positions of the 3D constellation ofobjects further comprises detecting the relative position of a planarsurface, the planar object comprising a distinct 2D pattern.